johansson



April 9, 1929- B. A. L. JOHANSSON 1,708,542

IECHANISM FOR CONVERTING OTIQN Filed Dec. 24, 1925 2 Sheets-Sheet 1April 9, 1929.

B. A. L. JOHANSSON 1,708,542

IECHANISM FOR CONVERTING MOTION Filed Dec. 24, 1925 2 Sheets-Sheet 2 as37 4? v 34 Patented Apr. 9, 1929.

UNITED STATES 3303 A. L. JOHANSSON, OF CHICAGO, ILLINOIS, ASSIGNOR TOHELIOS CORPORATION,

means PATENT OFFICE.

OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

MECHANISM FOR CONVERTING MOTION.

Application filed December 24, 1925. Serial No. 77,516.

M invention relates to mechanism for converting motion and has among itsother objects the production of mechanism of the kind described which isconvenient, compact, durable, efficient and satisfactory for usewherever found applicable.

A particular object of the invention is to provide mechanism of the kinddescribed which will be substantially noiseless in operation.

Another particular object of the invention is to provide mechanism ofthe kind described which will operate smoothly.

Still another particular object of the invention is to provide mechanismof the kind described in which wear is automatically compensated for sothat the mechanism continues to operate noiselessly and smoothly.

One form of the invention is embodied in motion picture apparatus forintermittently advancing the film and preferably comprises acontinuously driven cam having a follower to which an intermittentrotary motion is imparted by the earn, the follower comprising resilientmeans for insuring substantially perfect contact between the cam and thefollower, when the mechanism is in operation, so that the cam and itsfollower make substantially no noise. The cam preferably comprises aplurality of dwells and a portion which rotates the follower, and it ispreferably formed to increase the pressure between it and the followerwhen the follower is being rotated.

Many other objects and. advantages of the construction herein shown anddescribed will be obvious to those skilled in the art from thedisclosures herein given.

To this end my invention consists in the novel construction, arrangementand combination of parts herein shown and described, and moreparticularly pointed out in the claims. 7

in the drawings, wherein like reference characters indicate like orcorresponding parts:

Fig. 1 is a section taken through motion picture apparatus embodying theinvention;

Fig. 2 is a section taken on line 22 of Fig. 1;

Fig. 3 is a section-taken on line 33 of Fig. 1;

Fig. t is a section taken on line 4;& of

Fig. 1, the mechanism being shown in a changed position;

Fig. 5 is a section taken on line 55 of Fig. 4;

Fig. 6 is a developed View of a portion of a cam forming part of themechanism shown in Fig. 1; and

Fig. 7 is a section taken substantially on line 77 of Fig. 6.

In the drawings 1 have shown a preferred form of the invention embodiedin motion picture apparatus of the type shown and described in theco-pending application of John Proksa, Serial No. 17,336 filed March 21,1925. I have only illustrated so much of the mechanism as is necessaryto clearly disclose my invention, reference being made to the co-pendingapplication wherever necessary.

Referring for the present to Fig. 1 of the drawings, the referencecharacter 10 designates a shaft which is continuously driven by anysuitable mechanism (not shown), this mechanism being shown in theco-pending application as gearing which operatively connects the shaftto an electric motor; and keyed to the shaft 10 is a cam 11, or theequivalent, which is adapted to impart intermittent rotary motion to afollower or star wheel 16 mounted upon one end of a shaft 15, a sprocketdrum 16 being secured to the other end of the shaft 15. It is readilyunderstood that the sprocket drum 16 may be employed to intermittentlyadvance a film past light projecting apparatus, which is indicated at18. In this embodiment of the invention the shaft is rotatably journaledin a bushing 19 mounted in a casing 20 which is slidably journaled uponvertically disposed pins 21 carried by a casing 22. lhe details of thecasings 20 and 22 are not pertinent to this disclosure and will not befully described, the casings being fully shown and described in theabove mentioned co-pending application.

The cam 11 may be made of any suitable material and is preferably a discor wheel having a plurality of substantially circumferentially arrangeddwells or grooves 23 and 2 k in its periphery. However, the wells orgrooves 23 and 2% do not extend entirely around the cam, there beingstaggered breaks 25 and 26 in the grooves 23 and 24, respectively, (seeFig. 6). As best shown in Fig. 6, one end of the groove 23 is connectedto one end of the groove 24 by a curved groove 27, the curved groove 27being relatively short when compared with the length of the grooves 23and 24.

The follower or star wheel 14 preferably comprises a plurality of prongsor members 30 adapted to engage the grooves 23, 24 and 27, the membe 30comprising a frustroconical head 31 adapted to fit snugly in thegrooves. Each member 30 is preferably formed with a shank 33 slidablyjournaled in a hub 34 which comprises a housing member 35 formedintegral with the shaft 15, the housing member being provided with a cap36 secured to the member 35by a hollow head 36 formed upon one end of apin 37 screw-threaded into the shaft 15. Split bushings 39 arepreferably provided in the hub 34 for journaling the shanks 33. It willbe noted that the members 30 are radially disposed with respect to theaxis of rotation of the shaft 15 and that each member 30 is providedwith a frustro-conical head 42 at its inner end. The heads 42 areengaged by'a conical surface 44 formed upon a sleeve 45 which tends toseat in one end of a tubular member 46 seated in a depression 48 formedin the housing member 35, the tubular member being provided with acentral bore 49 to accommodate the pin 37. Notches 46 are provided inthe tubular member 46 for accommodatingthe heads 42. The. sleeve 45 isslidably journaled upon the pin 37 and is urged toward the member 46 bya compression spring 50, which has one of its ends bearing against thesleeve 45 and has the other of its ends bearing against the cap 36.Obviously, the spring 50 yieldingly prevents inward displacement of theprongs or members 30, but when one of the members 30 is forced towardthe axis of rotation of the shaft 15 in a manner hereinafter described,the sleeve 45'is displaced toward the cap 36 against the action of thespring 50.

The hub is provided with a plurality of fiat surfaces 52 adapted to rideupon a track 54 extending circiunferentially around the cam 11 from oneend of the groove 23 to one end of the groove 24, the track 54terminating at its ends in cam surfaces 55 which permit rotation of thefollower 14.

Briefly, the operation of the above described mechanisin issul'istantially as follows: Assuming that two of the heads 30 are ridingin the grooves 23 and 24, as illustrated in Fig. 3, and that one of theflat surfaces 52 is riding upon the track 54, as illustrated in the samefigure, the cam 11 may be rotated through an angle somewhat less than360 degrees without accompanying rotation of the follower 14. Thus, ifthe cam is rotating in the direction indicated by the arrow 57 in Fig.6, the heads 30 may ride in the grooves 23 and 24 from the dotted line58 to the dotted line 59 without causing rotation of the follower 14, itbeing understood that the cam makes nearly a complete revolution tobring the heads from the line 58 to the line 59. Then, asthe camcontinues to revolve, the head 30 engaging the groove 23 will ridethrough the groove 27 to the groove 24 andthe head 30 previouslyengaging with the groove 24 will pass out of engagement through thebreak 26. This will cause the follower 14 and the shaft 15 and thesprockets 16 to be revolved through an angle of 90 degrees, after whichthey will again remain stationary until the cam revolves through nearly360 degrees. Vi hen a head 30 enters the groove 24 by way of the groove27 another head 30 enters the groove 23 by way of the breal: 25 in thatgroove. Obviously, if the cam 11 is continuously rotated, anintermittent rotary motion will be imparted to the follower 14 and themechanism constrained to rotate therewith. The members 30 may be termedfollowers and are so identified in the claims, as the invention is notlimited to the particular construction shown and described.

The mechanism is preferably so constructed that the spring 50 isslightly compressed whena pair of the heads 30 are riding in the grooves23 and 24. In the illustrated embodiment of the invention, this pressurebetween the heads 30 and the walls of the grooves 23 and 24 isincreased, when the groove 27 approaches that head 30 which happens tobe riding in the groove 23. This increase in pressure is a function ofthe cam which is so designed that the groove 27 is spaced a suflicientdistance from the axis of rotation of the shaft 10 that a head 30passing through it will be held closer to the axis of the shaft 15 thanit is held when it passes through the major por tions of the grooves 23and 24, each groove 23 and 24 having its ends so formed that the heads30 will ride smoothly from the groove 23 into the groove 27, and thenceinto the groove 24. In practice, I have obtained good results by spacingthe groove 27 approximately .020 of an'inch farther away from the axisof rotation of the shaft 10 than it would be if the headswere notdisplaced, as described above, toward. the axis of the shaft 15 whenthey approach that groove. When the cam is so constructed, the headspass from the groove 23 into the groove 24 without clicking orchattering. Any wear in the heads 30 or the compensated for by thespring 50.

Having thus described my invention, itiis obvious that variousimmaterial modiiications may be made in the same without departing fromthe spirit of my invention; hence I do notwish to be understood aslimiting myself to the exact form, construcgrooves is lot messes 3?tion, arrangament and combination of parts herein shown and described,or uses mentioned.

lVhat I claim as new and desire to secure by Letters Patent is:

l. Mechanism for converting motion comprising a cam, a shaft, a followercarried by the shaft and operatively engaging the cam, said followerbeing movable radially with respect to the shaft, and resilient meanscarried by the shaft for holding the follower in engagement with the camunder pressure, said resilient means acting perpendicularly to thedirection of movement of the follower.

2. lifechanism for converting motion comprising a cam, a shaft, afollower carried by the shaft and operatively engaging the cam, meansfor slidably journaling said follower for movement radially with respectto the shaft and resilient means carried by the shaft for holding thefollower in engagement with the cam under pressure, said resilient meansacting perpendicularly to the direction of movement of the follower.

3. Mechanism for converting motion comprising a cam, a shaft, a movablefollower carried by the shaft and. operatively engaging the cam, andresilient means carried by the shaft for holding the follower inengagement with the cam under pressure, said. resilient means acting ina direction at an angle to the direction in which the follower isadapted to move, the cam having a prtion adapted to displace thefollower against the action of the resilient means.

4. Mechanism for converting motion comprising a cam, a shaft, a slidablyjominaled follower carried by the shaft to move radially thereof andoperatively engaging the cam, and resilient means disposed around theshaft for holding the follower in engagement with the cam underpressure, the (am having a portion adapted to dis place the followeragainst the action of the resilient means.

5. lviechanism for converting motion comprisinga cam, a shaft, aplurality of slidably journaled members constrained to rotate with theshaft, each of said members being intermittently engageable with thecam, atnd a spring common to said members for urging them toward the camwhen they are in engagement therewith.

(3. h lechanism for converting motion comprising a cam, means forrotating the cam, a follower engageable with the cam, a retatable shaft,means carried by the shaft for slidably journaling said follower topermit movement thereof radially with respect to the shaft, and asprilng carried by the shaft and acting in a direction parallel theretofor urging the follower toward the cam when it is engaging the earn.

7 Mechanism for converting motion comprising a cam, means for rotatingthe cam,

a follower engageable with the "am, a rotatable shaft, means carried bythe shaft for slid ably journaling said. follower to permit movementthereof radially with respect to the shaft, and a spring disposed aroundthe shaft for urging the follower toward the cam when it is engaging thecam.

8. lilleehanism for converting motion comprising a cam, means forrotating the cam, a plurality of followers engageable with the earn, arotatable shaft, means carried by the shaft for slidably journaling thefollowers to permit movement thereof radially with respect to the shaft,and resilient means acting in a direction parallel to said shaft forurging the followers toward the cam when they are engaging it.

9. Mechanism for converting motion comprising a cam, means for rotatingthe cam, a plurality of followers engageable with the cam, a rotatableshaft, means carried by the shaft for slldably journaling the followersto permit movement thereof radially with respect to t re shaft, and aspring common to all of the followers for urging them toward the camwhen they are engaging it.

10. Mechanism for converting motion comprising a cam, means for rotatingthe cam, a plurality of followers engageable with the cam, a rotatableshaft, means carried by the shaft for slidably journaling the followersto permit movement thereof radially with respect to the shaft, and aspring disposed around the shaft and commonto all of the followers forurging them toward the cam when they are engaging it.

11. Mechanism for converting motion comprising a cam, means for rotatingthe cam, a rotatable shaft having a hollow end, a follower engageablewith the cam and slidably journaled in the hollow end of said shaft topermit radial movement thereof with respect to the shaft, a memberslidably mounted in the hollow end of said shaft and cooperating withthe inner end of said follower to impart radial. movement thereto, and aspring mounted in the hollow end of said shaft for imparting movement tosaid member.

l2. Mechanism for converting motion comprising a cam, neans for rotatingthe cam, a rotatable shaft having a hollow end, a follower cngageablewith the cam and slidably journaled in the hollow end of said shaft topermit radial movement thereof with respect to the shaft, a membermounted in the hollow end of said shaft for sliding movement coaxialwith said shaft, said member coacting with the inner end of saidfollower so to transmit motion thereto in a direction perpendicular tothat of said memher, and a spring mounted in the hollow end of saidshaft for imparting movement to said member.

13. Mechanism for converting motion eomprising a cam, means for rotatingthe cam, a rotatable shaft having a hollow end, a plurality of followersengageable with the cam and slidably journaled in the hollow end of saidshaft to permit radial movement thereof with respect to the shaft, a pinmounted in the hollow end of said shaft, a member slidahly journaled onsaid pin for transmitting motion to said followers perpendicularly tothe motion of said member, 10

and a spring disposed around said pin and acting on said member toimpart motion thereto.

In testimony whereof, I have hereunto signed my name.

BROR A. L. JOHANSSON.

